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Electrochemical Machining of Gold Microstructures in LiCl/Dimethyl Sulfoxide
Author(s) -
Ma Xinzhou,
Bán Andreas,
Schuster Rolf
Publication year - 2010
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.200900713
Subject(s) - electrolyte , electrochemistry , dissolution , aqueous solution , materials science , cyclic voltammetry , electrochemical machining , electrode , surface micromachining , dimethyl sulfoxide , chemical engineering , inorganic chemistry , microstructure , analytical chemistry (journal) , chemistry , composite material , organic chemistry , fabrication , medicine , pathology , alternative medicine , engineering
LiCl/dimethyl sulfoxide (DMSO) electrolytes were applied for the electrochemical micromachining of Au. Upon the application of short potential pulses in the nanosecond range to a small carbon‐fiber electrode, three‐dimensional microstructures with high aspect ratios were fabricated. We achieved machining resolutions down to about 100 nm. In order to find appropriate machining parameters, that is, tool and workpiece rest potentials, the electrochemical behavior of Au in LiCl/DMSO solutions with and without addition of water was studied by cyclic voltammetry. In waterless electrolyte Au dissolves predominantly as Au(I), whereas upon the addition of water the formation of Au(III) becomes increasingly important. Because of the low conductivity of LiCl/DMSO compared with aqueous electrolytes, high machining precision is obtained with moderately short pulses. Furthermore, the redeposition of dissolved Au can be effectively avoided, since Au dissolution in LiCl/DMSO is highly irreversible. Both observations render LiCl/DMSO an appropriate electrolyte for the routine electrochemical micromachining of Au.